Rapid isolation of plant peroxidase. Purification of peroxidase a from Petunia

A rapid isolation procedure was developed for purification of peroxidase a from Petunia hybrida . Rapid isolation was possible since about 15% of the extracellular protein from stem tissue obtained by vacuum infiltration followed by centrifugation of the tissue represents peroxidase. Purification of peroxidase a from intercellular fluid was achieved by two acetone precipitation steps followed by DEAE-cellulose chromatography.
Three different forms of peroxidase were eluted from DEAE-cellulose at different NaCl concentrations. Isoelectric focusing showed, however, a pI of 3.8 for all three forms of peroxidase a . Only part of the peroxidase a enzymes bound to Concanavalin A indicating heterogeneity in the carbohydrate part. Homology of peroxidase a to the peroxidase G₁ group from tobacco is discussed.